Authorize.net CIM will provide Magento 'token' access to allow future transactions without the merchant storing any sensitive credit card data on their servers. Magento merchants who offer Authorize.Net as a payment gateway are allowing their customers to create customer accounts within Magento to facilitate a quicker checkout. The Authorize.Net CIM extension is a custom eCommerce payment solution to allow for stored billing data within the payment gateway rather than within the Magento platform.